<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"
                "http://www.w3.org/TR/REC-html40/loose.dtd">
<html>
<head>
  <title>Description of quadtfd</title>
  <meta name="keywords" content="quadtfd">
  <meta name="description" content="Generate Quadratic Time-Frequency Distributions">
  <meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
  <meta name="generator" content="m2html &copy; 2003 Guillaume Flandin">
  <meta name="robots" content="index, follow">
  <link type="text/css" rel="stylesheet" href="../m2html.css">
</head>
<body>
<a name="_top"></a>
<!-- menu.html hdocs -->
<h1>quadtfd
&nbsp;&nbsp;<img src="../mex.png" alt="Linux PC" border="0" title="Linux PC"></h1>

<h2><a name="_name"></a>PURPOSE <a href="#_top"><img alt="^" border="0" src="../up.png"></a></h2>
<div class="box"><strong>Generate Quadratic Time-Frequency Distributions</strong></div>

<h2><a name="_description"></a>DESCRIPTION <a href="#_top"><img alt="^" border="0" src="../up.png"></a></h2>
<div class="fragment"><pre class="comment"> Generate Quadratic Time-Frequency Distributions

 This function generates various members of quadratic time-frequency
 distributions. Predefined members can be specified, or a user defined
 kernel may be used.

 Usage:

     tfd = quadtfd( signal, lag_window_length, time_res, kernel
      [, kernel options] [,fft_length ] );

 kernel is one of: 'wvd', 'smoothed', 'specx', 'rm', 'cw', 'bjc', 'zam',
 'b' or 'mb'.

 where
     tfd

      The computed time-frequency distribution. size(tfd) will
      return [a, b], where a is the next largest power of two above
      fft_length, and b is floor(length(signal)/time_res) - 1.

     signal

      Input one dimensional signal to be analysed. An analytic signal
      is required for this function, however, if signal is real, a
      default analytic transformer routine will be called from this
      function before computing tfd.

    lag_window_length

      This is the data window length and controls the size of
      the kernel used for analysis (lag_window_length must    be
      odd). The kernel used will be defined from -(lag_window_length+1)/2
      to +(lag_window_length+1)/2 in both time and lag dimensions.

    time_res

      The number of time samples to skip between successive slices.

    kernel

      The determining kernel function.  kernel is a string defining
      a predefined kernel. 

      Predefined types:

             'wvd'         Wigner-Ville
             'smoothed'    Smoothed Wigner-Ville
             'specx'       Short-Time Fourier Transform
             'rm'          Rihaczek-Margenau-Hill
             'cw'          Choi-Williams
             'bjc'         Born-Jordan
             'zam'         Zhao-Atlas-Marks
             'b'           B-distribution
             'mb'          Modified B-distribution
             'emb'         Extended Modified B-distribution  
             

     kernel_options

      Some kernels require extra parameters:

         'smoothed'
             kernel_option = length of smoothing window
             kernel_option2 = type of smoothing window, one of: 'rect','hann','hamm','bart'
         'specx'
             kernel_option = length of smoothing window
             kernel_option2 = type of smoothing window, one of: 'rect','hann','hamm','bart'
         'cw'
             kernel_option = Smoothing parameter
         'zam'
             kernel_option = ZAM 'a' parameter
         'b'
             kernel_option = B-distribution smoothing parameter beta
         'mb'
             kernel_option = Modified B-distribution parameter alpha

         'emb'
             kernel_option = Extended Modified B-distribution parameters alpha, beta
        
         'ckd'
             
             kernel_option = Extended Modified B-distribution parameters alpha, beta
    fft_length

      Zero-padding at the FFT stage of the analysis may be specified by
      giving an fft_length larger than lag_window_length. If fft_length
      is not specified, or is smaller than the lag_window_length, then the
      next highest power of two above lag_window_length is used. If
      fft_length is not a power of two, the next highest power of two is
      used.



  See Also: <a href="analyt.html" class="code" title="">analyt</a></pre></div>

<!-- crossreference -->
<!-- removed -->
<!-- crossreference -->



<hr><address>Generated by <strong><a href="http://www.artefact.tk/software/matlab/m2html/" target="_parent">m2html</a></strong> &copy; 2016</address>
</body>
</html>